Cover for guiding a medium in an abrasive disk

ABSTRACT

The invention relates to a grinding-wheel cover ( 3 ) for grinding wheels with a support body ( 1 ) and a grinding layer ( 2 ) arranged at an edge or face for edge or face use in grinding, a grinding-wheel cover being provided for forming cavities on the grinding body, wherein the grinding-wheel cover ( 3 ) additionally being.provided with partitions, recesses or cutouts ( 5 ) for increasing the pressure of the cooling and or lubricating medium.

The invention relates to a cover for a grinding wheel with a support body and a grinding layer mounted on an outer edge or on a face for edge or face use in grinding procedures, a grinding-wheel cover being provided for forming a cavity on the grinding body.

Whenever a workpiece, independent of its structure and of its grinding layer, is being ground there are high temperatures in the work area of the grinding tool that can be controlled with a cooling and lubricating medium.

Grinding wheels with covers are known. Thus, for example U.S. Pat. No. 3,777,443, U.S. Pat. No. 2,470,350, DE 1,502,607, and U.S. 5,846,125 describe grinding-wheel covers forming chambers for holding cooling or lubricating mediums and mounted on a support body. In all these constructions, during the grinding process the cooling or lubricating medium unilaterally unevenly swashes in the hollow chamber due to inertia or gravity, which can lead to an imbalance of the grinding body and irregular spinning.

The corresponding cooling or lubricating medium of all these constructions only gets up to the angular speed of the grinding wheel slowly or not at all, which leads to significantly higher wear caused by the off-balance operation and to a reduced cooling or lubricating at the point of application. Even partitions for guiding the medium as disclosed in U.S. Pat. No. 5,423,717 cannot counter this effect.

Therefore, it is the object of the invention to improve the cooling and lubrication even of grinding wheels used to date without significant refitting costs. This is achieved in that the cover for the formation of cavities is provided with further partitions, recesses or cutouts that receive the cooling and lubricating medium, increase the pressure of the medium and convey it to the necessary points of application during the grinding process.

By means of this conveying system for the cooling and lubricating medium, the medium can be more directly fed to the points of application. In addition both the grinding body and the grinding wheel holder are cooled more uniformly and more effectively. This results in better grinding and a higher quality workpiece as well as increased grinding-tool life.

It is a further feature of the invention that the grinding-wheel cover additionally has a deflection formation for moving the medium. The partitions, recesses or cutouts in the grinding-wheel cover according to a further feature of the invention can be designed such that they narrow in their flow cross section inside to outside, which leads to a pressure increase of the medium due to centrifugal force. Furthermore, the partitions, recesses or cutouts are uniformly distributed over the whole circumference of the grinding-wheel cover, preferably in a star-shaped arrangement. The ends of such a stellate array of recesses end at respective bores in the grinding body in order to be able to transport the medium with increased pressure to the point of application.

The grinding-wheel cover can be composed of widely varied materials and produced in the different processing and machining procedures (e.g. cutting, machining, casting). This grinding-wheel cover with its central opening serves for the creation of a cavity and thus for the medium inlet into the inner body of the grinding wheel construction. The grinding-wheel cover is provided with partitions, recesses or cutouts which increase the pressure of the cooling and lubricating medium within the grinding wheel and force the medium to assume the angular speed of the grinding wheel. Thus, an unbalance caused by a swashing medium is avoided. The medium is transported to the designated point of application by means of bores, openings or recesses in the grinding body and in the grinding layer. The grinding-wheel cover can be detachably or non-detachably connected to the grinding-wheel body, for example by welding, soldering, bolting, gluing or by means of retaining rings.

By means of the invention, known and in-use grinding wheels can be improved without large modification efforts when produced or when installed later, particularly regarding improved grinding characteristics, longer operational life, less machine downtime, less machining time, improved repeating exactness and reduced heating of the grinding wheel and the workpiece as well as improved surface quality of the workpiece. Thanks to the improved lubricating and cooling effect there are no structural modifications regarding the processed materials.

The drawing shows an illustrated embodiment of the object of the invention.

FIG. 1 shows a detailed view of the grinding-wheel cover for an edge-type grinding wheel.

FIG. 2 shows a section according to line A of FIG. 1.

FIG. 3 shows a detailed view of a grinding wheel with a mounted grinding-wheel cover with a possible design of the recesses on the grinding-wheel cover. Furthermore, a possible design of the bores for the medium discharge in the grinding body and grinding layer is illustrated.

FIG. 4 shows a longitudinal section through an edge-type grinding wheel with the grinding-wheel cover according to the invention mounted thereon.

The grinding wheel shown in FIGS. 2 and 3, consisting of a support body 1 and a grinding layer 2, as well as of the grinding-wheel cover 3 shown in FIGS. 1 and 2, by the central opening 4 of which the medium gets into the grinding wheel. By partitions, recesses or cutouts 5 the medium is forced to assume the angular speed of the grinding wheel and the medium is conveyed to the point of application via discharge bores 6 in the grinding body and in the grinding layer. The deflection chamfers 7 serve for the better transport of the cooling and lubricating medium through the central opening 4. 

1-6. (canceled)
 7. A grinding wheel comprising: a support body centered on and rotatable about an axis and having an axially directed face surface and a radially outwardly directed edge surface; a grinding layer fixed to one of the surfaces of the body; and a cover ring fixed to the face surface of the body and forming a single intake opening and a plurality of radially extending cavities opening radially inward and dimensioned to compress and feed radially outward a liquid medium fed to the intake opening while the wheel is rotating about its axis.
 8. The grinding wheel defined in claim 7 wherein the intake opening opens radially inward.
 9. The grinding wheel defined in claim 7 wherein the ring has an inner edge forming the opening formed with a bent-out lip.
 10. The grinding wheel defined in claim 7 wherein the cavities are of flow cross section that decreases radially outward.
 11. The grinding wheel defined in claim 10 wherein the cavities are distributed angularly uniformly about the axis.
 12. The grinding wheel defined in claim 10 wherein. the body is formed with respective radially extending bores having inner ends opening into the cavities and outer ends opening at the one surface.
 13. A grinding wheel comprising: a disk-shaped support body centered on and rotatable about an axis, having an axially directed face surface and a radially outwardly directed edge surface, and formed with an array of angularly equispaced and radially extending bores each having a radial outer end opening at one of the surfaces and a radial inner end; a grinding layer fixed to the one surface of the body; and a cover ring fixed to the face surface of the body and forming a single radially inwardly open intake opening and a plurality of radially extending and angularly equispaced cavities opening radially inward at the opening, of cross-sectional size decreasing radially outward, and connected to the inner ends of the bores, whereby liquid fed to the intake opening while the wheel is rotating about the axis is driven outward through the cavities and respective bores and is pressurized increasingly radially outward. 